• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.1051-1052
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• 2006

In this paper, we propose a puncturing scheme to design low-density parity-matrix (LDPC) codes for unequal error protection (UEP). Two different puncturing schemes are compared. Simulation results show that proposed puncturing scheme outperforms regular puncturing scheme for more important bits. Future work is to find an optimized puncturing patten for UEP irregular LDPC codes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2207-2213
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• 2010

A new scheme for variable structure control design which is based on eigenvalues assignment of sliding mode is developed. In conventional methods, generally, specific type of system matrix like canonical or regular form is required to construct a switching surface. Furthermore, the methods are not explicit. The new method in this paper solved the problems. No special type of system matrix is required and very explicit. It is shown that the switching surface can be constructed and determined uniquely without any dependency on the system form. The proposed method is based on the fact that the dynamics of sliding mode is determined by system zeros. Finally, a numerical example is given to verify the validity of the results studied in this paper.

• Earthquakes and Structures
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• v.18 no.5
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• pp.609-623
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• 2020

This paper presents a displacement-based seismic design procedure for new structures with fluid viscous dampers and/or for existing structures, where these devices are required as a retrofit measure and damage control. To consider the non-proportional damping produced by these devices in a conventional modal spectral analysis, the effect of the fluid viscous dampers is approximated as the sum of a proportional damping matrix and a complementary matrix which is representative of non-proportional damping matrix. To illustrate the application of this procedure and evaluate the performance of structures designed with the procedure proposed, five regular plane frames: 8, 12, 17, 20 and 25-storey, and an 8-storey building are designed. The seismic demands used for design and validation were the records obtained at the SCT site during the 1985 Michoacan earthquake, and that of the 2017 Morelos - Puebla earthquake obtained at the Culhuacan site, both stations located on soft soil sites. To validate the procedure proposed, the performances and damage distributions used as design targets were compared with the corresponding results from the nonlinear step-by-step analyses of the designed structures subjected to the same seismic demands.

• Journal of the Society of Naval Architects of Korea
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• v.59 no.5
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• pp.296-305
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• 2022

In order to investigate maneuvering characteristics of KCS in waves, captive model test in regular waves was conducted. Purpose of the test is measuring maneuvering hull forces when ship is maneuvering in waves. Model test was carried out using CPMC (Computerized Planar Motion Carriage) of ocean engineering basin in KRISO (Korea Research Institute of Ships and Ocean engineering). Total 6 degrees-of-freedom motion were fixed by two points supporting captive model test device, which is specially designed for this test. This system estimates 6 degrees-of-freedom forces and moments through 12 strain gauge signals. Mapping matrix from strain gauge signals to 6 degrees-of-freedom forces and moments was derived by a well-organized calibration test. Static drift test was conducted in calm sea and in regular waves with various wave conditions. Hydrodynamic coefficients related to drift angle were extracted for each wave conditions, and the effect of waves on course stability was analyzed.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.293-301
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• 2009

Analytical results of a fixed concentration of Pb, Cd and Cr in the synthetic copper standard solution (RMs) for using the matrix no matched standard calibration curve at various wavelength by ICP showed that accuracy (140 $\sim$ 1,070% in case of Pb) is very poor at all wavelengths because of the Cu matrix effect. Analytical results of a fixed concentration of Pb, Cd and Cr in the different concentration solutions of Cu showed that found values were on the increase or decrease as the rate of a regular equation as the concentration of Cu was increased. Accuracies by the Cu matching method in the analysis of Pb, Cd and Cr in the synthetic copper standard solution (RMs) were higher than 99.9%.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.10
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• pp.1880-1885
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• 2007

In this paper, we propose the method that improve the performance of the Mowse. Mowse is the tool of the peptide mass fingerprinting that is used the identification of protein. In Mowse, frequency factor matrix is generated to regular interval for protein and peptide mass and the value of each elements is calculated to frequency of peptide. We propose new method for calculation of exact scoring value maintaining same size of matrix. The proposed method is that decide interval of matrix considering distribution of protein database. That is, interval of matrix is decided to small in many value of protein mass and is decided to large in few value of protein mass. We present the performance result both Mowse scoring method and the proposed scoring method.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.457-473
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• 2005

In each step of the quasi-minimal residual (QMR) method which uses a look-ahead variant of the nonsymmetric Lanczos process to generate basis vectors for the Krylov subspaces induced by A, it is necessary to decide whether to construct the Lanczos vectors $v_{n+l}\;and\;w{n+l}$ as regular or inner vectors. For a regular step it is necessary that $D_k\;=\;W^{T}_{k}V_{k}$ is nonsingular. Therefore, in the floating-point arithmetic, the smallest singular value of matrix $D_k$, ${\sigma}_min(D_k)$, is computed and an inner step is performed if $\sigma_{min}(D_k)<{\epsilon}$, where $\epsilon$ is a suitably chosen tolerance. In practice it is absolutely impossible to choose correctly the value of the tolerance $\epsilon$. The subject of this paper is to show how discrete stochastic arithmetic remedies the problem of this tolerance, as well as the problem of the other tolerances which are needed in the other checks of the QMR method with the estimation of the accuracy of some intermediate results. Numerical examples are used to show the good numerical properties.

• Fibers and Polymers
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• v.7 no.4
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• pp.358-366
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• 2006

Thermotropic liquid crystal polymer (TLCP)-reinforced poly(butylene terephthalate) (PBT) composites were prepared by melt processing. The improvement in the mechanical properties and the processability of the PBT/TLCP composites was attributed to the reinforcing effect by TLCP phase and its well distribution in the PBT matrix. X-ray diffraction results demonstrated that a slow cooling process leads to the thicker lamellar structures and the formation of more regular crystallites in the composites. The incorporation of TLCP improves not only the tensile strength and flexural modulus but also the heat distortion temperature (HDT) of the PBT/TLCP composites. The HDT values of the composites were dependent on TLCP content. The improvement in the HDT values of the PBT/TLCP composites may be explained in terms with the increased flexural modulus, the development of more regular crystalline structures, and the enhancement of the ability of the composites to sustain the storage modulus by TLCP phase. In addition, the simple additivity rule makes it possible to predict the HDT values of the PBT/TLCP composites.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.2
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• pp.83-90
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• 1997

This study was performed to demonstrate the effect of linear or nonlinear contrast enhancement on subtraction images. Three different textures were radiograped on dental film. The first radiograph was taken without the presence of an object. the second, which showed trabucular bone, was taken of the molar area of a human. the third radiograph was taken of the coronal part of molars. Each film was digitized into a 1312 x 1024 pixel x 8 bit depth matrix by means of a Nikon 35 mm film scanner(LS-3510AF, Japan) with fixed gain and internal dark current correction to maintain constant illumination. The scanner was interfaced to a Macintosh Le ill computer(Apple Computer, Charlotte, N.C) This resulted in three pairs of images, including different textures-plain, bone and enamel. Digital regular, linearly and nonlinearly enhanced subtraction was performed. Computer software was ,used to simulate lesions in the shape of a 2D-Gaussian curve on each of a pair of images. The each subtraction images were presented in a random sequence to two groups of 10 observers(students and dentists). ROC analysis was used to compare observer performance. The following results were obtained ; 1. All of LCE subtraction, equalized subtraction and regular subtraction images of plain texture were diagnosed the best by far. 2. The data revealed a siginificant LCE effect in both the student group and the expert group. 3. Clinical expertise was a helphul factor for the observers in this study.

• Journal of the Korean Ceramic Society
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• v.23 no.2
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• pp.13-20
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• 1986

Composite polycrystals including ${\gamma}$-$6Bi_2O_3$.$SiO_2$ crystal which have needlelike regular structure are useful for the high resolution optical devices. For the purpose of obtaining the composite polycrystals described above the melts of eutectic composition in the three eutectic systems including $6Bi_2O_3$.$SiO_2$ composition were unidirectionally solidified at a rate of 0.05 and 0.25 cm/h under a thermal gradient of 10$0^{\circ}C$/m. Composite polycrystals of relatively regular structure in which needlelike ${\gamma}$-$6Bi_2O_3$.$SiO_2$ crystals were arrayed in parallel with $2Bi_2O_3$.$B_2O_3$ crystal matrix were obtained when the eutectic melt of $6Bi_2O_3$.$SiO_2 -2Bi_2O_3$.$B_2O_3$ system was solidified at a rate of 0.25 cm/h. Partial structural irregularity however was found in the obtained composite polycrystals.